What operation is performed here? When to shift bits and when to shift binary points? To what value scaling is done?

I am using TI's Piccolo F28027 C2000 MCU for the application of Field Oriented Control of PMSM motor using Embedded Coder Support Package.

I have referred an example for Model based Code Development from file exchange - "c28027pmsmfoc_ert".

When currents Ia/Ib are sampled through ADC, then these current inputs are scaled. Below is the screenshot of that.

Please explain me when to shift bits and when to shift binary points?

And what has been done here, and to what values they are scaled ?

Any help is appreciated.

Answer 1

[Darshan Pandit]

Hi Sanjeev,

The F28027 is a fixed point processor, and when we read currents from ADCs, these are scaled from ADC Counts to per-unit system applied for embedded system.

I'd suggest you to go through the following post, where I've explained answer to a similar question:

https://stackoverflow.com/questions/47466291/iq-math-calculation

Also, if you would like to understand the per-unit system concepts, applied to embedded systems, you may refer to the following post:

https://e2e.ti.com/support/microcontrollers/c2000/f/171/t/876296

Once you go through these, please let us know if you still have any doubts.